The incorrect positioning of teeth or the misalignment of teeth between the upper dental arch and lower dental arch are known as malocclusions. Malocclusions are categorized by dental health professionals in three classifications: Class I—the jaw relationship is normal but individual teeth (whether located on the upper or lower dental arch) have problems such as spacing, crowding, etc., and do not achieve a good fit with the corresponding teeth on the opposite arch. Class II—commonly referred to as an overbite, the upper jaw is not in proper position, and an increased projection of the upper teeth in front of the lower teeth results. This lack of contact between the front teeth allows them to keep erupting or extruding, from the gum line into the mouth until they contact something, usually the palate. This over-extrusion, especially of the lower front teeth, requires the orthodontist to place intrusive forces on these teeth during treatment. Finally, Class III—wherein the upper dental arch rests behind the lower dental arch when the mouth is closed, commonly referred to as an underbite.
The orthodontic treatment of the aforementioned malocclusions often employs the use of the ubiquitous braces. Unfortunately, braces (that is the combination of brackets, placed on individual teeth, and an archwire connecting each bracket to guide the movement of teeth) do not correct the relationship of the upper and lower dental arches (Class II and Class III malocclusions). Additional orthodontic appliances, that provide either a pulling or pushing force must be used in order to restrict or encourage (by pulling or pushing) the jaw into its proper bite position, actually forcing the jawbones and muscles to physically adapt or “learn” the correct bite positioning.
Several bite-correcting appliances are used, often concurrently (if possible) with braces to limit the length of time of orthodontic treatment. Discussed in detail in U.S. Pat. No. 4,708,646, incorporated by reference herein, bite-correcting appliances include patient-removable appliances such as rubber bands, headgear, and molded mouthpieces. The downfall of all patient-removable appliances is that they are removable by the patient. The patient simply forgets to replace the appliance after eating, for example, thereby creating unpredictably in both the length of time of treatment, and even the treatment results, since a non-compliant patient can undo the gains of earlier treatment or produce no results.
Non-removable bite-correcting appliances are also employed. One of the most common is the “Herbst” device, developed in the early 1900's by Dr. Herbst. The Herbst device and Herbst-like devices are comprised of a rigid bar, in which each end of the bar is affixed to the lower and upper dental arches, forcing the lower dental arch forward into the desired occlusion position. The bar exerts excessive forces at its attachment points, transmitting the entire biting force of the teeth (100 pounds) to the attachment points. As a result, stainless steel crowns have to be cemented to the anchoring (attachment) teeth; the brackets of braces simply cannot handle the force. In addition to being difficult to install and generating excessive forces, another drawback, to the Herbst and Herbst-like devices is that their rigidity and placement makes both the chewing of food and hygiene incredibly difficult for the patient, as the devices cross through the area where the food is chewed.
The device disclosed in U.S. Pat. No. 4,708,646, often referred to as the “Jasper Jumper” alleviated many of the Herbst shortcomings. The rigid bar was replaced by a coiled spring, encased in a rubber sheath with attachment flanges at each end. One attachment flange would be secured to the bracket located on an upper molar tube of the patient's braces, while the second flange was secured on the archwire of the patient's braces located on the lower jaw. The Jumper generated a flexible pushing force, light enough (4-8 ounces) to be connected to braces, and generating a corrective force along the normal growth line of the face, allowing minimal discomfort for the patient. The flex-point of the spring was located in the middle of the spring, allowing the patient to better chew food and clean his/her teeth. The Jumper design, however, was prone to failure, simply breaking in the patient's mouth.
Additionally, the Jumper, the Herbst, and the Herbst clones all cross directly through the food chewing zone, when people eat. The food bolus (ball) is processed on the front side of the first molars and the second premolars as a half-inch ball. All of the aforementioned appliances, whether rigid or flexible, cross directly in the path of the food bolus making chewing and brushing cumbersome and uncomfortable.
To date, the bite-correcting appliances have been inadequate from both the physician's and patient's view, requiring improvement in durability, ease of installation/replacement, wearability, and first and foremost, function; by removing the extrusive force vectors that the prior art appliances place on the jaws/teeth; so as to obtain the desired bite correction in a short timeframe.